%  Copyright (c) 2017, Amos Egel (KIT), Lorenzo Pattelli (LENS)
%                      Giacomo Mazzamuto (LENS)
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%===============================================================================
%> @brief Returns the associated Legendre function constructed from a
%>        coefficient table. This function is only used for testing.
%>
%> @param ct (float): cos theta
%> @param st (float): sin theta
%> @param l (int): degree of Legendre function
%> @param m (int): order of Legendre function
%> @param coeff_tab (3-dim float array): coefficient table as genereated by
%>        Plm_coefficients().
%>
%> @retval Plm (float): Legendre function value
%===============================================================================
function Plm = check_legendre(ct,st,l,m,coeff_tab)

Plm = 0;
jj = 0;
for lbd = (l-m):-2:0
    jj = jj+1;
    Plm = Plm + st^m * ct^lbd * coeff_tab(l+1,m+1,jj);
end
end
